Page:Life Movements in Plants.djvu/166

136 Averrhoa the longitudinal velocity is of the order of 1 mm. per second.

The record of the transmitted effect of stimulus is found to exhibit a remarkable preliminary variation. This was detected by my delicate recorders, which gave magnifications from fifty to hundred times. I shall give a detailed account of a typical experiment carried out with Averrhoa carambola, which will bring out clearly the characteristic effects of Indirect Stimulus.

Experiment 47.—Stimulus of electric shock applied at a point on the long petiole of Averrhoa causes successive fall of pairs of leaflets. In the experiment to be described one

52.—Effect of indirect Stimulus on leaflet of Averrhoa carambola. Stimulus was applied at the short vertical line. Successive dots at intervals of one second. Note the positive response preceding the negative.